Keep only the last attempt for retry_verification

[i3/i3lock] / i3lock.c

diff --git a/i3lock.c b/i3lock.c
index a836240e97c8dbbc430bf68ffffddd5914b4419b..fd4d1d294275b54c5bc59ae816914c36676de149 100644 (file)
--- a/i3lock.c
+++ b/i3lock.c
@@ -6,6 +6,8 @@
  * See LICENSE for licensing information
  *
  */
+#include <config.h>
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <pwd.h>
@@ -17,6 +19,7 @@
 #include <xcb/xcb.h>
 #include <xcb/xkb.h>
 #include <err.h>
+#include <errno.h>
 #include <assert.h>
 #ifdef __OpenBSD__
 #include <bsd_auth.h>
@@ -43,6 +46,7 @@
 #include "cursors.h"
 #include "unlock_indicator.h"
 #include "randr.h"
+#include "dpi.h"
 
 #define TSTAMP_N_SECS(n) (n * 1.0)
 #define TSTAMP_N_MINS(n) (60 * TSTAMP_N_SECS(n))
@@ -178,7 +182,7 @@ static void clear_password_memory(void) {
     /* A volatile pointer to the password buffer to prevent the compiler from
      * optimizing this out. */
     volatile char *vpassword = password;
-    for (int c = 0; c < sizeof(password); c++)
+    for (size_t c = 0; c < sizeof(password); c++)
         /* We store a non-random pattern which consists of the (irrelevant)
          * index plus (!) the value of the beep variable. This prevents the
          * compiler from optimizing the calls away, since the value of 'beep'
@@ -441,6 +445,12 @@ static void handle_key_press(xcb_key_press_event_t *event) {
             return;
         default:
             skip_repeated_empty_password = false;
+            // A new password is being entered, but a previous one is pending.
+            // Discard the old one and clear the retry_verification flag.
+            if (retry_verification) {
+                retry_verification = false;
+                clear_input();
+            }
     }
 
     switch (ksym) {
@@ -470,8 +480,12 @@ static void handle_key_press(xcb_key_press_event_t *event) {
             if (ksym == XKB_KEY_h && !ctrl)
                 break;
 
-            if (input_position == 0)
+            if (input_position == 0) {
+                START_TIMER(clear_indicator_timeout, 1.0, clear_indicator_cb);
+                unlock_state = STATE_NOTHING_TO_DELETE;
+                redraw_screen();
                 return;
+            }
 
             /* decrement input_position to point to the previous glyph */
             u8_dec(password, &input_position);
@@ -486,7 +500,7 @@ static void handle_key_press(xcb_key_press_event_t *event) {
             return;
     }
 
-    if ((input_position + 8) >= sizeof(password))
+    if ((input_position + 8) >= (int)sizeof(password))
         return;
 
 #if 0
@@ -626,6 +640,36 @@ void handle_screen_resize(void) {
     redraw_screen();
 }
 
+static bool verify_png_image(const char *image_path) {
+    if (!image_path) {
+        return false;
+    }
+
+    /* Check file exists and has correct PNG header */
+    FILE *png_file = fopen(image_path, "r");
+    if (png_file == NULL) {
+        fprintf(stderr, "Image file path \"%s\" cannot be opened: %s\n", image_path, strerror(errno));
+        return false;
+    }
+    unsigned char png_header[8];
+    memset(png_header, '\0', sizeof(png_header));
+    int bytes_read = fread(png_header, 1, sizeof(png_header), png_file);
+    fclose(png_file);
+    if (bytes_read != sizeof(png_header)) {
+        fprintf(stderr, "Could not read PNG header from \"%s\"\n", image_path);
+        return false;
+    }
+
+    // Check PNG header according to the specification, available at:
+    // https://www.w3.org/TR/2003/REC-PNG-20031110/#5PNG-file-signature
+    static unsigned char PNG_REFERENCE_HEADER[8] = {137, 80, 78, 71, 13, 10, 26, 10};
+    if (memcmp(PNG_REFERENCE_HEADER, png_header, sizeof(png_header)) != 0) {
+        fprintf(stderr, "File \"%s\" does not start with a PNG header. i3lock currently only supports loading PNG files.\n", image_path);
+        return false;
+    }
+    return true;
+}
+
 #ifndef __OpenBSD__
 /*
  * Callback function for PAM. We only react on password request callbacks.
@@ -770,8 +814,7 @@ static void raise_loop(xcb_window_t window) {
     xcb_generic_event_t *event;
     int screens;
 
-    if ((conn = xcb_connect(NULL, &screens)) == NULL ||
-        xcb_connection_has_error(conn))
+    if (xcb_connection_has_error((conn = xcb_connect(NULL, &screens))) > 0)
         errx(EXIT_FAILURE, "Cannot open display\n");
 
     /* We need to know about the window being obscured or getting destroyed. */
@@ -852,7 +895,7 @@ int main(int argc, char *argv[]) {
     while ((o = getopt_long(argc, argv, optstring, longopts, &longoptind)) != -1) {
         switch (o) {
             case 'v':
-                errx(EXIT_SUCCESS, "version " VERSION " © 2010 Michael Stapelberg");
+                errx(EXIT_SUCCESS, "version " I3LOCK_VERSION " © 2010 Michael Stapelberg");
             case 'n':
                 dont_fork = true;
                 break;
@@ -997,6 +1040,8 @@ int main(int argc, char *argv[]) {
 
     screen = xcb_setup_roots_iterator(xcb_get_setup(conn)).data;
 
+    init_dpi();
+
     randr_init(&randr_base, screen->root);
     randr_query(screen->root);
 
@@ -1006,7 +1051,7 @@ int main(int argc, char *argv[]) {
     xcb_change_window_attributes(conn, screen->root, XCB_CW_EVENT_MASK,
                                  (uint32_t[]){XCB_EVENT_MASK_STRUCTURE_NOTIFY});
 
-    if (image_path) {
+    if (verify_png_image(image_path)) {
         /* Create a pixmap to render on, fill it with the background color */
         img = cairo_image_surface_create_from_png(image_path);
         /* In case loading failed, we just pretend no -i was specified. */
@@ -1015,8 +1060,8 @@ int main(int argc, char *argv[]) {
                     image_path, cairo_status_to_string(cairo_surface_status(img)));
             img = NULL;
         }
-        free(image_path);
     }
+    free(image_path);
 
     /* Pixmap on which the image is rendered to (if any) */
     xcb_pixmap_t bg_pixmap = draw_image(last_resolution);